Calculate Your One Rep Max
Wondering how strong you really are in a certain lift? That’s where the One Rep Max (1RM) comes in — it's the max weight you can lift once, with good form. It’s often used for big compound lifts like squats, deadlifts or bench press. Instead of actually trying it in the gym (which can be risky), you can estimate it safely with this calculator.
There are a few formulas used to calculate 1RM. This tool gives you results from two of the most trusted:
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Epley – great for beginners and lower rep ranges
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Brzycki – often used by strength-focused lifters
Both are accurate enough to guide your training, so you can lift smarter and track real progress!
Your estimated 1 Rep Max will appear here
* Please note: This is only an estimate of your 1 rep max. Always listen to your body and use caution. Your actual max may vary depending on your energy levels and technique.
FAQ
How does the Max Rep Calculator work?
This 1 rep calculator estimates your one rep max (1RM) based on the weight you lifted and the number of reps you completed (up to 10). It uses two trusted formulas – Epley and Brzycki – both backed by training data. These give you a safe and realistic idea of how much weight you could lift for just one rep, without actually having to do it in the gym.
Is 1RM calculation accurate?
While no formula is perfect, these 1 rep max calculator methods are surprisingly close — when used for lifts with 10 reps or fewer. They're widely used in strength training to estimate max potential and guide smart programming. For most people, they’re accurate enough to track progress and set training goals safely.
What is One Rep Max used for in training?
Your one rep max is often used to build personalized training plans. Coaches and athletes use it to set lifting percentages — like 70%-85% of your 1RM for hypertrophy, or 85–90% for strength work. It helps you train smarter, not just harder.
Can I use this Max Rep Calculator for any exercise?
Yes! You can calculate one rep max for any lift — from squats and deadlifts to overhead press or even bicep curls. But it’s most accurate for big compound movements like squats, bench press or deadlifts. For isolation exercises, use it more as a guideline than an exact number.